1. Technical Field
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel in which exhaust performance is improved.
2. Related Art
In recent years, the plasma display panel has been in the spotlight as a replacement for the cathode-ray tube display. The plasma display panel is a device in which discharge gas is filled and sealed between two substrates with a plurality of electrodes, and then a discharge voltage is applied to them, thus generating ultraviolet rays. In the device, fluorescent layers formed in a predetermined pattern are excited by the ultraviolet rays to form a desired image.
The plasma display panel comprises a back substrate and a front substrate disposed opposite to each other. A plurality of address electrodes are arranged on an upper surface of the back substrate, and these address electrodes are buried by first dielectric layers. Partition walls partition discharge cells in a matrix shape on an upper surface of the first dielectric layers. Although partition walls of stripe shape were widely used, a closed type of partition wall, quadrilateral in shape, has been primarily used in recent years in order to reduce the possibility of cross-talk between discharge cells.
An inside surface of the discharge cells partitioned by these partition walls is coated to a predetermined thickness with fluorescent layers.
The front substrate is a transparent substrate into which visible rays can be transmitted, is mainly made of glass, and is combined with the back substrate. Pairs of sustain electrodes which intersect the address electrodes are formed on a bottom surface of the front substrate. In the pairs of sustain electrodes, one sustain electrode is an X electrode, and the other sustain electrode is a Y electrode.
The pairs of sustain electrodes are buried by transparent second dielectric layers, and protective layers are formed on the bottom surface of the second dielectric layers. Since the protective layers emit secondary electrons inside the discharge cells with increased efficiency, they lower the discharge voltage applied between electrodes and protect the electrodes.
In the case of a closed type of partition walls, gas communication between the discharge cells is not smooth. Therefore, it is difficult to exhaust impure gas or to inject discharge gas.